Alcool, Alcoolisme, Aloolisation

I thi s treat i se publis h e d in 195 6 , the Fr e n c h d e mogra phe r Ledermann proposed his “single distribution theory” of alcohol consumption. In subsequent decades, this still controversial theo­ ry has stimulated research that has contributed to a fundamental reconsideration of heavy drinking and alcoholism. Public health advocates have used Ledermann’s theory to justify higher taxes and other limits on the availability of alcohol to the public.

I n thi s treat i se publis h e d in 195 6 , the Fr e n c h d e mogra phe r Ledermann proposed his "single distribution theory" of alcohol consumption. In subsequent decades, this still controversial theo ry has stimulated research that has contributed to a fundamental reconsideration of heavy drinking and alcoholism. Public health advocates have used Ledermann's theory to justify higher taxes and other limits on the availability of alcohol to the public.
The Single Distribution Theory. Ledermann's earlier work in cluded a series of studies on the relationship between mortality patterns and the general level of alco hol consumption in a population, both o ve r t i m e a n d a c r o s s Fr an c e . H e demonstrated that regions in which average consumption was high tended to have relatively high mortality from li ver c i rrhosis and other a l cohol related causes, suggesting that the p r e va l en c e o f h e a v y d r i n ki n gand drinkingrelated health conse quences-in a population is closely related to the general level of drinking in that population.
In Alcool, Alcoolisme, Alcooli sation, Ledermann offered several general concepts, two of which are de scribed below, that fit his epidemio logical findings but went much farther: 1. A graph depicting the percentage of drinkers at each level of alcohol con sumption (from one drink per year to thousands of drinks per year) at a given point in time would have the character istic shape of the lognormal curve. This asymetric curve would show a single peak (indicating the highest concentra tion of people). The "tail" extending to the right of the peak (along the X axis) would indicate a smaller proportion of people who consume a greater amount of alcohol. Among them are the people whose levels of drinking place them at risk for different levels of alcohol prob lems, ranging from alcohol dependence and organ damage to early death.
2. Any two populations with the same per capita alcohol consumption will have the same prevalence of heavy drinking (e.g., more than 50 liters per year). And in any two populations with different consumption levels, the population with the higher per capita consumption will have a greater preva lence of heavy drinking. Although there seems to be a popular belief that some societies have high average alco hol consumption but low levels of alcohol abuse (France, perhaps), examples of such societies do not exist. In fact, according to Ledermann, the per capita consumption for a population group has a onetoone relationship with the prevalence of heavy drinking. 1 It is probably best to consider Ledermann's two concepts as bold inferences he made from the data he gathered in his earlier epidemi ological work. As it turns out, subsequent research has proven that Ledermann's intuition in developing these concepts was sound.

Subsequent Research.
The single distribution theory achieved prominence through the work of deLint, Schmidt, and their col leagues at the Addiction Research Foundation in Toronto. Their analysis of cirrhosis mortality patterns had demonstrated a close sta 1 Ledermann proposed a formula relating the mean of the (lognormal) drinking distri bution to its standard deviation. Given this formula, knowledge of a population's aver age consumption was sufficient to characterize completely the drinking distribution. tistical correspondence with per capita alcohol consumption, a result for which Ledermann's theory offered a powerful explanation. During the late 1960's, deLint and colleagues undertook a program to test the single distribution theory by examining the distribution of alcohol consumption in several data sets. They concluded that the lognormal distribution provided a reasonable approximation of the distribution of alcohol consumption (e.g., deLint and Schmidt 1968). Several Nordic researchers continued this work by analyzing the results of the distribution of alcohol consumption from general population surveys (Mäkelä 1969;Skog 1971). The two groups col laborated in writing Alcohol Control Policies in Public Health Perspective (Bruun et al. 1975), a project sponsored by the World Health Organization. This important monograph summarized the accumulated findings and spelled out their implications for primary prevention of alcoholrelated problems.
How well have Ledermann's two propositions held up to em pirical scrutiny? Studies of a considerable number and variety of populations have accorded well with Ledermann's first concept. The distribution of alcohol consumption does indeed have the characteristic shape of the lognormal curve-a single peak and a long tail to the right, indicating that a small proportion of the pop ulation consumes a disproportionally large amount of the total al cohol consumption for that population (Schmidt and Popham 1978;Skog 1980). This result is not surprising, because it also ap plies to the distributions for most consumer commodities. 2 The second proposition is much more important and controver sial, and it too has fared well over time. There is a remarkable "lawfulness" (i.e., consistency) to the distribution of alcohol con sumption. For example, Skog compared several population surveys for different countries and found that the percentage of respondents reporting that they consumed more than 10 centiliters of alcohol per day "fit" Ledermann's theory very well (Skog 1985). As predicted, this percentage was about the same for populations with similar av erage alcohol consumption levels, and the percentage increased with the average consumption. The latter relationship is quadratic: If pop ulation A has twice the average consumption of population B, then A has about four times the prevalence of heavy drinking.

Significance for Policy.
Ledermann's thesis challenged the accept ed wisdom of his day. At that time, most scientists and opinion lead ers accepted the perspective that heavy drinking was primarily a concern because of its association with alcoholism. Alcoholics were viewed as a distinct subgroup whose drinking was largely beyond the control of alcohol availability or social context. Particularly in the United States, any proposal to raise taxes or otherwise reduce average drinking was viewed as pointless and unscientific, because these measures were based on Prohibitionera temperance thinking, the failure of which discredited such beliefs (Room 1984).
In contrast, Ledermann took the epidemiologist's view, that whether or not heavy drinkers were in some sense alcoholics, they were at risk for a variety of lifethreatening illnesses. Ledermann also asserted that drinking, even heavy drinking, was influenced by the drinker's social environment. Indeed, an implication of the sin gle distribution theory is that any intervention reducing per capita consumption necessarily reduces the prevalence of heavy drinking. 3 Furthermore, this theory suggests the futility 4 of attempting to re duce the prevalence of heavy drinking without reducing normal consumption levels. Thus the primary prevention of health prob lems stemming from chronic heavy drinking becomes closely linked with reducing overall consumption within the whole popula tion. Such measures as raising taxes on alcoholic beverages, reduc ing density of outlets that sell alcoholic beverages, and restricting alcoholic beverage advertising become, in this perspective, the key weapons in combatting the diseases resulting from chronic heavy drinking (Edwards et al. 1994).
Ledermann's intuition concerning the distribution of alcohol consumption captured important elements of this phenomenon. Heavy drinkers, whether or not they are alcoholics, are not a dis tinct group immune to social and economic pressure but rather are part of a continuum with moderate and light drinkers. There is both good news and bad news here for alcohol control policy. Ledermann's work shows that the heavy drinkers will reduce their drinking if-but only if-the others cut back too. ■